Catheters and catheter systems

Abstract

The present invention provides a catheter and catheter system that can efficiently deliver drugs from inside to outside a blood vessel, even in blood vessels where direct catheter insertion is difficult. [Solution] The catheter according to the present disclosure comprises: a catheter body having an internally partitioned administration lumen through which an administered substance can pass, and having an outlet formed therein for discharging the administered substance from the administration lumen; a deformable member located radially outside the catheter body and attached to the catheter body so as to be elastically deformable in the longitudinal direction of the catheter body; an ultrasonic transducer supported by the catheter body or the deformable member and capable of transmitting ultrasonic waves toward the distal side in the longitudinal direction; and a valve member capable of opening and closing the administration lumen in accordance with the longitudinal deformation of the deformable member.

Description

[Technical Field]

[0001] The present disclosure relates to a catheter and a catheter system. [Background Art]

[0002] For example, blood-organ barriers that control the passage of substances through intercellular spaces, such as the blood-brain barrier (abbreviated as BBB), are known. At the blood-organ barrier, tight junctions where vascular endothelial cells are closely adhered and connected are formed. Therefore, it is said that drug delivery is inhibited by the blood-organ barrier when delivering a drug from the intravascular space through the vascular endothelium, for example. Patent Document 1 describes a treatment method in which an irradiation part of an elongated medical instrument provided with an irradiation part capable of emitting ultrasonic waves is moved to the vicinity of the blood-brain barrier in a blood vessel, ultrasonic waves are emitted from the irradiation part near the blood-brain barrier, and stimulation is applied to nerves or surrounding tissues from outside the blood vessel to widen the blood-brain barrier. [Prior Art Literature] [Patent Literature]

[0003] [Patent Document 1] Japanese Unexamined Patent Application Publication No. 2019-110982 [Summary of the Invention] [Problems to be Solved by the Invention]

[0004] However, there are blood vessels into which direct insertion of a catheter is difficult, such as cerebral blood vessels and microvessels of coronary arteries, for example. The treatment method described in Patent Document 1 cannot widen the blood-organ barrier in such blood vessels.

[0005] An object of the present disclosure is to provide a catheter and a catheter system that can improve the efficiency of drug delivery from the inside of a blood vessel to the outside of the blood vessel even for blood vessels into which direct insertion of a catheter is difficult. [Means for Solving the Problems]

[0006] A catheter as a first aspect of this disclosure is (1) A catheter body comprising an internally partitioned administration lumen through which the administered substance can pass, and an outlet formed therein for discharging the administered substance from the administration lumen, A deformable member is attached to the catheter body so as to be located radially outside the catheter body and elastically deformable in the longitudinal direction of the catheter body, An ultrasonic transducer supported by the catheter body or the deformable member, capable of transmitting ultrasonic waves toward the distal end in the longitudinal direction, A catheter comprising a valve member capable of opening and closing the administration lumen in accordance with the longitudinal deformation of the deformable member.

[0007] A catheter as one embodiment of the present disclosure is (2) The catheter body has a side hole connected to the administration lumen. The valve member is connected to the deformation member through the side hole, The valve member is the catheter described in (1) above, which moves in the longitudinal direction in accordance with the longitudinal deformation of the deformable member, thereby enabling the opening and closing of the administration lumen.

[0008] A catheter as one embodiment of the present disclosure is (3) The valve member is Valve body and, The catheter according to (2) above, comprising a valve support portion that supports the valve body and is connected to the deformation member through the side hole.

[0009] A catheter as one embodiment of the present disclosure is (4) The valve member is such that the deformable member receives an external force directed toward the distal side in the longitudinal direction and deforms in the longitudinal direction against elastic force, thereby enabling the administration lumen to be switched from a closed state to an open state. The ultrasonic transducer is a catheter according to any one of (1) to (3) above, which is capable of transmitting ultrasound toward the distal side in the longitudinal direction when the administration lumen is closed.

[0010] A catheter as one embodiment of the present disclosure is (5) The ultrasonic transducer is the catheter described in (4) above, which is capable of transmitting ultrasound toward the distal side in the longitudinal direction when the administration lumen is in the open state.

[0011] A catheter as one embodiment of the present disclosure is (6) The valve member is such that the deformable member receives an external force directed toward the distal side in the longitudinal direction and deforms in the longitudinal direction against elastic force, thereby enabling the administration lumen to be switched from an open state to a closed state. The ultrasonic transducer is a catheter according to any one of (1) to (3) above, which is capable of transmitting ultrasound toward the distal side in the longitudinal direction when the administration lumen is closed.

[0012] A catheter as one embodiment of the present disclosure is (7) The aforementioned deformed member is The proximal end is fixed to the catheter body, and the bellows-like portion is elastically deformable by expanding and contracting in the longitudinal direction, A catheter according to any one of (1) to (6) above, comprising: a sliding part attached to the tip of the bellows-like part, which moves in the longitudinal direction by sliding against the outer surface of the catheter body as the bellows-like part expands and contracts.

[0013] A catheter as one embodiment of the present disclosure is (8) The catheter according to any one of (1) to (7) above, wherein the ultrasonic transducer is supported by the deformable member.

[0014] A catheter according to one embodiment of the present disclosure is: (9) the discharge port is formed on a distal end surface of the catheter body, further comprising a mesh-like cylindrical body attached to the catheter body such that the mesh-like cylindrical body can change its shape between a stored configuration stored in the administration lumen and a protruding configuration protruding to the distal side in the longitudinal direction through the discharge port, The catheter according to any one of (1) to (8) above, wherein in the protruding configuration, the mesh-like cylindrical body is expandable to a position radially outward of the ultrasonic transducer.

[0015] A catheter system according to a second aspect of the present disclosure is: (10) the catheter according to any one of (1) to (9) above, and a catheter system, comprising: a control device connectable to the catheter and capable of controlling transmission of ultrasonic waves from the ultrasonic transducer based on an open / closed state of the administration lumen.

Effects of the Invention

[0016] According to the present disclosure, it is possible to provide a catheter and a catheter system that can improve the efficiency of drug delivery from the inside of a blood vessel to the outside of the blood vessel even for a blood vessel into which direct insertion of a catheter is difficult.

Brief Description of Drawings

[0017] [Figure 1] It is a diagram showing a catheter system as one embodiment of the present disclosure. [Figure 2A] It is a perspective view of the distal end portion of the catheter as one embodiment of the present disclosure shown in Figure 1, showing a state where a bellows-shaped portion of the deformable member is contracted. [Figure 2B]Figure 1 is a perspective view of the tip of a catheter as one embodiment of the present disclosure, showing the bellows-like portion of the deformable member in an extended state. [Figure 3A] Figure 2A is a cross-sectional view of the tip of the catheter. [Figure 3B] Figure 2B is a cross-sectional view of the tip of the catheter. [Figure 4] This is a cross-sectional view taken at the position of line II in Figure 3A. [Figure 5A] This is a cross-sectional view of the tip of a catheter as one embodiment of the present disclosure, showing the valve member in a state where the administration lumen is open. [Figure 5B] Figure 5A is a cross-sectional view of the tip of the catheter, showing the valve member closing the administration lumen. [Figure 6] This figure shows a catheter system as one embodiment of the present disclosure, including a catheter as one embodiment of the present disclosure. [Modes for carrying out the invention]

[0018] Hereinafter, embodiments of the catheter and catheter system relating to this disclosure will be described with reference to the drawings. In each figure, identical components are denoted by the same reference numerals.

[0019] Figure 1 shows a catheter system 300 as one embodiment of the catheter system according to the present disclosure. As shown in Figure 1, the catheter system 300 comprises a catheter 100 as one embodiment of the catheter according to the present disclosure, a control device 301, a drug supply unit 302, and a bubble supply unit 303. Figure 1 shows the catheter 100 inserted into a blood vessel BV.

[0020] In the catheter system 300, a drug can be administered into the blood vessel BV through the catheter 100 from the drug supply unit 302. Furthermore, the catheter system 300 can administer microbubbles X, also an administered substance, into the blood vessel BV through the catheter 100 from the bubble supply unit 303. Here, microbubbles X refer to tiny bubbles with a diameter of 10 μm or less. For example, known ultrasound contrast agents can be used as microbubbles X. Examples of ultrasound contrast agents include Optison®, Definity®, Sonovue®, Levovist®, Imagent, and Sonazoid®. The drug and microbubbles X administered into the blood vessel BV are delivered downstream in the direction of blood flow within the blood vessel BV (hereinafter referred to as "downstream of the blood vessel BV") by the blood flow within the blood vessel BV. In the catheter system 300, the ultrasound transducer 50 of the catheter 100 (described later) transmits ultrasound toward the downstream of the blood vessel BV. This allows ultrasound to be irradiated onto microbubbles X that have been delivered downstream of the blood vessel BV by the blood flow within the blood vessel BV. When ultrasound is irradiated onto microbubbles X, they vibrate by contracting and expanding. As a result, in the region within the blood vessel BV where the microbubbles X vibrate due to ultrasound irradiation, the vibrating microbubbles X push apart the tight junctions where vascular endothelial cells are tightly bound together. This creates a small gap for drug delivery outside the blood vessel BV. Thus, with the catheter system 300, drug delivery via the vascular endothelium from within the blood vessel BV to cells and tissues outside the blood vessel BV can be made more efficient in the region downstream of the blood vessel BV from the region where the catheter 100 is located within the blood vessel BV. Therefore, even in regions within the blood vessel BV where it is difficult to directly insert the catheter 100, such as cerebral blood vessels and coronary artery microvessels, drug delivery from within the blood vessel BV to cells and tissues outside the blood vessel BV can be made more efficient.

[0021] [Catheter 100] As described above, the catheter 100 may be used, for example, to administer a drug as an administered substance into a blood vessel BV. Also, as described above, the catheter 100 may be used to administer microbubbles X as an administered substance in addition to a drug. Furthermore, as will be described in detail later, the catheter 100 is equipped with an ultrasonic transducer 50 capable of irradiating ultrasound onto the microbubbles X administered into the blood vessel BV. In addition, the catheter 100 is configured to mechanically control the timing of the presence or absence of blood flow in the blood vessel BV in accordance with the pulse, and the timing of the administration of the administered substance into the blood vessel BV. Therefore, with the catheter 100, the administered substance to be administered into the blood vessel BV can be efficiently delivered downstream of the blood vessel BV by being carried by the blood flow. Therefore, with the catheter 100, the treatment using the catheter system 300 described above can be efficiently performed.

[0022] The following describes the details of catheter 100.

[0023] Figures 2A and 2B are perspective views of the tip of the catheter 100. Figures 2A and 2B show different states of the tip of the catheter 100. Figure 2A shows the bellows-like portion 31 of the deformable member 30, which will be described later, in a contracted state. Figure 2B shows the bellows-like portion 31 of the deformable member 30, which will be described later, in an extended state. Figure 3A is a cross-sectional view of the tip of the catheter 100 shown in Figure 2A. Figure 3B is a cross-sectional view of the tip of the catheter 100 shown in Figure 2B. Figures 3A and 3B are cross-sectional views of the catheter 100 along the longitudinal direction of the catheter body 10, which will be described later. Figure 4 is a cross-sectional view at the position of line II in Figure 3A.

[0024] As shown in Figures 3A and 3B, the catheter 100 comprises a catheter body 10, a deformation member 30, an ultrasonic transducer 50, and a valve member 70.

[0025] As shown in Figures 3A to 4, the catheter body 10 has an internally partitioned administration lumen 10a through which the administered substance can pass. The catheter body 10 also has an outlet 10a1 through which the administered substance can be discharged from the administration lumen 10a. Therefore, the administered substance is delivered from the administration lumen 10a into the blood vessel BV (see Figure 1) through the outlet 10a1. As shown in Figures 2A to 3B, the outlet 10a1 in this embodiment is formed on the tip surface 10b of the catheter body 10.

[0026] Hereinafter, in the catheter 100, the longitudinal direction of the catheter body 10 will be described as "longitudinal direction A of the catheter body 10" or simply "longitudinal direction A". Within longitudinal direction A, the catheter insertion direction from the proximal end to the distal end of the catheter body 10 will be described as "distal A1", and the catheter withdrawal direction from the distal end to the proximal end of the catheter body 10 will be described as "proximal A2". In the catheter 100, the circumferential direction of the catheter body 10 will be described as "circumferential direction B of the catheter body 10" or simply "circumferential direction B". In the catheter 100, the radial direction of the catheter body 10 will be described as "radial direction C of the catheter body 10" or simply "radial direction C".

[0027] As shown in Figures 1 to 4, the deformable member 30 is located radially outward from the catheter body 10 in the direction C. The deformable member 30 is attached to the catheter body 10 so as to be elastically deformable in the longitudinal direction A. As will be described in detail later, the deformable member 30 is configured to elastically deform in the longitudinal direction A when subjected to pressure from the blood flow generated in accordance with the heartbeat within the blood vessel BV (see Figure 1) into which the catheter 100 is inserted. More specifically, the deformable member 30 of this embodiment is subjected to pressure from the blood flow generated in accordance with the heartbeat and stretches in the longitudinal direction A against elastic force. On the other hand, the deformable member 30 of this embodiment is not subjected to pressure from the blood flow when there is no blood flow generated in accordance with the heartbeat. Therefore, from the state in which it has stretched in the longitudinal direction A due to the pressure from the blood flow, it contracts in the longitudinal direction A due to elastic force (restoring force). In this way, the deformable member 30 is configured to expand and contract in the longitudinal direction A in accordance with the presence or absence of blood flow.

[0028] As shown in Figures 1 to 4, the ultrasonic transducer 50 is supported by the deformable member 30. However, the ultrasonic transducer 50 may also be supported by the catheter body 10. The ultrasonic transducer 50 is capable of transmitting ultrasound toward the distal side A1 in the longitudinal direction A. In this embodiment, the ultrasonic transducer 50 is supported on the tip surface of the deformable member 30.

[0029] As shown in Figures 3A to 4, the valve member 70 can open and close the administration lumen 10a as the deformation member 30 deforms in the longitudinal direction A. Specifically, in this embodiment, the valve member 70 closes the administration lumen 10a when the deformation member 30 contracts in the longitudinal direction A (see Figures 3A and 4). Also, in this embodiment, the valve member 70 opens the administration lumen 10a when the deformation member 30 extends in the longitudinal direction A (see Figure 3B).

[0030] However, the valve member 70 may be configured such that the deformable member 30 contracts in the longitudinal direction A to open the administration lumen 10a, and extends in the longitudinal direction A to close the administration lumen 10a. Details of this configuration will be described later (see Figures 5A and 5B).

[0031] Thus, the catheter 100 is equipped with a valve member 70 that can open and close the administration lumen 10a in accordance with the elastic deformation of the deformable member 30 in the longitudinal direction A. Therefore, by configuring the deformable member 30 to be elastically deformable in the longitudinal direction A by the pressure received from the blood flow in the blood vessel BV (see Figure 1), it is possible to synchronize or prevent the timing of blood flow generation (hereinafter simply referred to as "blood flow timing") and the timing of administering the substance from the administration lumen 10a through the outlet 10a1 into the blood vessel BV (hereinafter simply referred to as "administration timing").

[0032] Specifically, the catheter 100 of this embodiment is configured so that the blood flow timing and the administration timing coincide. More specifically, the valve member 70 of this embodiment is configured to close the administration lumen 10a when there is no blood flow (see Figure 3A). Conversely, the valve member 70 of this embodiment is configured to open the administration lumen 10a when there is blood flow (see Figure 3B).

[0033] However, the catheter 100 may be configured so that the blood flow timing and the administration timing do not coincide. Details of catheters configured so that the blood flow timing and administration timing do not coincide will be described later (see Figures 5A and 5B).

[0034] By configuring the catheter 100 so that the blood flow timing and administration timing are synchronized or not synchronized, it is possible to efficiently deliver the drug from within the vascular BV (see Figure 1) to cells and tissues outside the vascular BV via the vascular endothelium in areas within the vascular BV where direct insertion of the catheter 100 is difficult. The details of this will be explained below.

[0035] In the catheter 100 of this embodiment, as shown in Figure 3A, the administered substance is not administered when there is no blood flow. In contrast, in the catheter 100 of this embodiment, as shown in Figure 3B, the administered substance is administered when there is blood flow. Therefore, immediately after administration, the administered substance enters the bloodstream and moves to the downstream side of the blood vessel BV (see Figure 1). Thus, with the catheter 100 of this embodiment, it is possible to prevent the administered substance from accumulating near the outlet 10a1 of the catheter body 10. As a result, for example, when administering a drug and microbubbles X (see Figure 1) as the administered substance, the drug and microbubbles X can be efficiently delivered to the area downstream of the blood vessel BV from the position where the catheter 100 is inserted in the blood vessel BV. Ultrasound transmitted from the ultrasonic transducer 50 toward the distal side A1 in the longitudinal direction A propagates along the blood vessel BV, reflecting off it, to branch vessels, small blood vessels, etc. downstream of the blood vessel BV. Therefore, by transmitting ultrasound from the ultrasonic transducer 50 toward the distal A1, the ultrasound can be efficiently irradiated onto the microbubbles X (see Figure 1) that have traveled downstream of the blood vessel BV on the blood flow. In other words, the ultrasound vibrates the microbubbles X in the region downstream of the blood vessel BV from the position where the catheter 100 is inserted, and the drug can be efficiently delivered from inside the blood vessel BV to cells and tissues outside the blood vessel BV through the vascular endothelium in that region. That is, the catheter 100 of this embodiment makes it possible to efficiently deliver drugs in regions within the blood vessel BV where it is difficult to directly insert the catheter 100.

[0036] The same applies to catheters configured so that the blood flow timing and administration timing do not coincide, but the details will be described later (see Figures 5A and 5B).

[0037] Next, further details of the catheter 100 of this embodiment will be described.

[0038] As shown in Figure 1, the catheter body 10 of this embodiment comprises a tubular body 20 that can be inserted into a blood vessel BV, and a hub 21 to which the proximal end of the tubular body 20 is fixed. The administration lumen 10a of this embodiment is partitioned across the tubular body 20 and the hub 21. The outlet 10a1 of this embodiment is formed on the tip surface of the tubular body 20. In other words, the tip surface 10b of the catheter body 10 of this embodiment is the tip surface of the tubular body 20.

[0039] As shown in Figures 3A and 3B, the catheter body 10 of this embodiment, in addition to the administration lumen 10a described above, also comprises an insertion lumen 11 through which a signal line 51 electrically connected to the ultrasonic transducer 50 can be inserted. The insertion lumen 11 is also partitioned across the tubular body 20 and the hub 21. The tubular body 20 of this embodiment has a side wall that partitions the administration lumen 10a on its inside. In the tubular body 20 of this embodiment, the insertion lumen 11 is formed within the wall of the side wall. However, the signal line 51 may be arranged to extend, for example, along the outer surface of the tubular body 20 of the catheter body 10.

[0040] In this embodiment, the catheter body 10 has a side hole 10a2 connected to the administration lumen 10a. As will be described in detail later, the valve member 70 in this embodiment is connected to the deformation member 30 through the side hole 10a2 of the catheter body 10. The side hole 10a2 is formed at the tip of the catheter body 10. The side hole 10a2 in this embodiment is a slit extending in the longitudinal direction A. In addition, the catheter body 10 in this embodiment has a plurality of side holes 10a2. The plurality of side holes 10a2 are arranged at intervals in the circumferential direction B. More specifically, the side hole 10a2 in this embodiment is formed in the side wall of the tip of the tubular body 20. The side hole 10a2 in this embodiment penetrates the side wall of the tubular body 20 in the radial direction C.

[0041] As shown in Figures 3A and 3B, the catheter body 10 of this embodiment is provided with an annular flange 20a that protrudes inward in the radial direction C. More specifically, the tubular body 20 of the catheter body 10 of this embodiment is provided with an annular flange 20a that protrudes inward in the radial direction C. The annular flange 20a of this embodiment is located proximal A2 to the slit which serves as the side hole 10a2. As shown in Figures 3A and 3B, the annular flange 20a defines a through hole 20a1 that penetrates in the longitudinal direction A on the inside of the radial direction C. This through hole 20a1 is part of the administration lumen 10a. The valve member 70 of this embodiment can occlude the administration lumen 10a by covering this through hole 20a1 from the distal side A1 in the longitudinal direction A (see Figure 3A). Furthermore, the valve member 70 of this embodiment is spaced apart distally from the through hole 20a1 to A1, and does not cover the through hole 20a1 from the distal side A1 in the longitudinal direction A, thereby allowing the administration lumen 10a to be opened (see Figure 3B).

[0042] Furthermore, as shown in Figures 3A and 3B, the catheter body 10 of this embodiment is equipped with an annular flange 20b that protrudes outward in the radial direction C. More specifically, the tubular body 20 of the catheter body 10 of this embodiment is equipped with an annular flange 20b that protrudes outward in the radial direction C. As shown in Figures 3A and 3B, the base end of the bellows-shaped portion 31 of the deformable member 30, which will be described later, is fixed to the annular flange 20b.

[0043] As shown in Figure 1, the hub 21 includes a first connection part 21a that can be connected to the control device 301. The hub 21 also includes a second connection part 21b that can be connected to the drug supply unit 302 and the bubble supply unit 303. Furthermore, the hub 21 includes a hub body 21c that is connected to the tips of the first connection part 21a and the second connection part 21b, and to which the base end of the tubular body 20 is fixed. The control device 301 is electrically connected to the ultrasonic transducer 50 via a signal line 51 (see Figure 3A, etc.) by being connected to the first connection part 21a. This allows the control device 301 to control the transmission of ultrasound from the ultrasonic transducer 50. The drug supply unit 302 can supply drug to the administration lumen 10a (see Figure 3A, etc.) by being connected to the second connection part 21b. The bubble supply unit 303 can supply fluid containing microbubbles X to the administration lumen 10a (see Figure 3A, etc.) by being connected to the second connection part 21b. The drug and microbubbles X supplied from the drug supply unit 302 and the bubble supply unit 303 to the administration lumen 10a are administered into the blood vessel BV through the outlet 10a1.

[0044] The tubular body 20 is preferably formed from a flexible material, but the material is not particularly limited. Examples of constituent materials for the tubular body 20 include various thermoplastic elastomers such as styrene-based, polyolefin-based, polyurethane-based, polyester-based, polyamide-based, polyimide-based, polybutadiene-based, trans-polyisoprene-based, fluororubber-based, and chlorinated polyethylene-based materials. Combinations of one or more of these (polymer alloys, polymer blends, laminates, etc.) can also be used. Furthermore, a hydrophilic lubricating coating layer that exhibits lubricity when wet may be placed on the outer surface of the tubular body 20.

[0045] The constituent materials of the hub 21 are not particularly limited, but examples include polyolefins such as polyethylene, polypropylene, and ethylene-vinyl acetate copolymer, polyurethane, polyamide, polyester, polycarbonate, polybutadiene, polyvinyl chloride, and polyacetal.

[0046] The deformable member 30 of this embodiment is elastically deformable in the longitudinal direction A in response to the pressure of blood flow within the blood vessel BV (see Figure 1). In other words, the catheter 100 of this embodiment does not have an operating member for elastically deforming the deformable member 30 in the longitudinal direction A. An operating member could be, for example, a wire whose tip is attached to the deformable member 30 and which extends along the catheter body 10. In other words, because the catheter 100 of this embodiment does not have the above-mentioned operating member, users such as surgeons using the catheter 100 cannot manipulate the elastic deformation of the deformable member 30 located within the blood vessel BV in the longitudinal direction A from outside the body. In other words, the spring constant in the longitudinal direction A of the deformable member 30 of this embodiment is set so that it can elastically deform in the longitudinal direction A in response to the pressure of blood flow. The spring constant in the longitudinal direction A of the deformable member 30 may be set, for example, so that the deformable member 30 is elastically deformed in the longitudinal direction A by the pressure of blood flow with a flow velocity of 10 mm / s generated by pulsation.

[0047] As shown in Figures 1 to 3B, the deformable member 30 of this embodiment includes a bellows-shaped portion 31 that can be elastically deformed by expanding and contracting in the longitudinal direction A, and a sliding portion 32.

[0048] The proximal end of the bellows portion 31 is fixed to the catheter body 10. Specifically, in this embodiment, the proximal end of the bellows portion 31 is fixed to the annular flange 20b of the tubular body 20 of the catheter body 10. In this embodiment, the bellows portion 31 is cylindrical, covering the entire circumferential area B of the tubular body 20 on the outside of the radial direction C, but is not limited to this configuration. The bellows portion 31 may be, for example, a strip, covering only a part of the circumferential area B of the tubular body 20 on the outside of the radial direction C. Alternatively, multiple such strip-shaped bellows portions 31 may be arranged in the circumferential area B. Multiple strip-shaped bellows portions 31 may be connected in the circumferential area B, or they may be spaced apart in the circumferential area B. However, from the viewpoint of the stability of elastic deformation of the deformable member 30 in the longitudinal direction A, it is preferable that the bellows portion 31 be cylindrical.

[0049] The sliding portion 32 is attached to the tip of the bellows portion 31. The sliding portion 32 is movable in the longitudinal direction A by sliding against the outer surface of the catheter body 10 as the bellows portion 31 expands and contracts in the longitudinal direction A. In this embodiment, the sliding portion 32 is an annular portion supported on the outer surface of the catheter body 10. Therefore, the sliding portion 32 in this embodiment is supported on the outer surface of the catheter body 10 and is slidable on the outer surface of the catheter body 10. In this embodiment, the outer surface of the catheter body 10 on which the sliding portion 32 is supported and on which the sliding portion 32 slides is the outer peripheral surface of the tubular body 20 in the radial direction C of the catheter body 10. Therefore, the sliding portion 32 in this embodiment is movable in the longitudinal direction A by sliding against the outer peripheral surface of the tubular body 20 as the bellows portion 31 expands and contracts in the longitudinal direction A.

[0050] Figure 3A shows the bellows-shaped portion 31 in its natural state, not subjected to an external force in the longitudinal direction A. In contrast, Figure 3B shows the bellows-shaped portion 31 in a deformed state, subjected to an external force in the longitudinal direction A and elastically deformed against an elastic force (restoring force). As shown in Figures 3A and 3B, the bellows-shaped portion 31 of this embodiment can be extended in the longitudinal direction A by moving its tip to the distal side A1 in the longitudinal direction A relative to the proximal end fixed to the catheter body 10. Conversely, the bellows-shaped portion 31 of this embodiment can be contracted in the longitudinal direction A by moving its tip to the proximal side A2 in the longitudinal direction A relative to the proximal end fixed to the catheter body 10. In other words, the deformable member 30 of this embodiment can be extended in the longitudinal direction A by the bellows-shaped portion 31 extending toward the distal side A1 in the longitudinal direction A against an elastic force. Furthermore, the deformable member 30 of this embodiment is expandable and contractible in the longitudinal direction A by the elastic force of the bellows-shaped portion 31 contracting toward the proximal side A2 in the longitudinal direction A.

[0051] The bellows-like portion 31 is not particularly limited in its constituent material, as long as it can be elastically deformed by expanding and contracting in the longitudinal direction A. Examples of constituent materials for the bellows-like portion 31 include rubber materials such as silicone rubber.

[0052] The material of the sliding part 32 is not particularly limited, but it is preferable that the sliding resistance with the outer surface of the catheter body 10 is low. For this reason, various resin materials such as polyacetal (POM) and fluororesins such as polytetrafluoroethylene can be used as the material of the sliding part 32.

[0053] As described above, the ultrasonic transducer 50 is capable of transmitting ultrasonic waves toward the distal side A1 in the longitudinal direction A. Furthermore, the ultrasonic transducer 50 of this embodiment does not transmit ultrasonic waves toward the outward side in the radial direction C. More specifically, the ultrasonic transducer 50 of this embodiment is capable of transmitting ultrasonic waves only toward the distal side A1 in the longitudinal direction A. As shown in Figures 1 to 4, the ultrasonic transducer 50 of this embodiment is supported by the deformable member 30. More specifically, the ultrasonic transducer 50 of this embodiment is supported by the sliding part 32. More specifically, the ultrasonic transducer 50 of this embodiment is supported by the tip surface of the sliding part 32.

[0054] Furthermore, the ultrasonic transducer 50 in this embodiment can be electrically connected to the control device 301 via a signal line 51. As shown in Figures 3A and 3B, the signal line 51 is inserted through the insertion lumen 11 of the catheter body 10. The tip of the signal line 51 is connected to the ultrasonic transducer 50 from the position of the side hole 10a2. The tip of the signal line 51 may, for example, pass inside the sliding portion 32 of the deformable member 30 and be connected to the ultrasonic transducer 50. Alternatively, the tip of the signal line 51 may be arranged, for example, along the surface of the sliding portion 32 of the deformable member 30.

[0055] The transmission of ultrasound from the ultrasonic transducer 50 can be controlled by the control device 301. In the catheter system 300 of this embodiment shown in Figure 1, the transmission of ultrasound from the ultrasonic transducer 50 may be performed regardless of, for example, the open / closed state of the administration lumen 10a. Specifically, the control device 301 may control the ultrasonic transducer 50 to transmit ultrasound in both states: when the valve member 70 is closing the administration lumen 10a (see Figure 3A) and when the valve member 70 is opening the administration lumen 10a (see Figure 3B). This makes it easier for the control device 301 to control the ultrasonic transducer 50.

[0056] Furthermore, the control device 301 may, for example, execute the transmission of ultrasound from the ultrasonic transducer 50 when the valve member 70 is closing the administration lumen 10a (see Figure 3A), and not execute the transmission of ultrasound from the ultrasonic transducer 50 when the valve member 70 is opening the administration lumen 10a (see Figure 3B). In this way, the microbubbles X (see Figure 1) discharged from the outlet 10a1 at the administration timing can be delivered downstream of the vascular BV (see Figure 1) by being carried by the blood flow, and then ultrasound can be transmitted from the ultrasonic transducer 50. Therefore, drug delivery through the vascular endothelium in areas within the vascular BV where direct insertion of the catheter 100 is difficult can be made more efficient. This control is particularly useful when drug delivery through the vascular endothelium in areas downstream of the catheter 100 in the vascular BV is not intended near the outlet 10a1 of the catheter 100.

[0057] The opening and closing of the administration lumen 10a by the valve member 70 may be detected by, for example, a sensor 25. In other words, the control device 301 may control the transmission of ultrasonic waves from the ultrasonic transducer 50 based on the detection result of the sensor 25. The sensor 25 only needs to be able to detect the opening and closing of the administration lumen 10a by the valve member 70, and its configuration is not particularly limited. The sensor 25 may be, for example, a distance sensor held by the catheter body 10 that can detect the amount of deformation of the deformation member 30 in the longitudinal direction A. If the amount of deformation of the deformation member 30 in the longitudinal direction A can be detected, the closed state of the administration lumen 10a can be detected. Alternatively, the sensor 25 may be, for example, a contact sensor held by the catheter body 10 that can detect the position of the sliding part 32 by contacting the sliding part 32. Such a contact sensor may be arranged so as to contact the sliding part 32 only when the administration lumen 10a is in the closed state. This makes it possible to detect the closed state of the administration lumen 10a. Furthermore, the catheter 100 may be configured such that the conductivity between the control device 301 and the ultrasonic transducer 50 changes as the deformation of the deformable member 30 in the longitudinal direction A changes. The signal line 51 and the ultrasonic transducer 50 may be configured to be in contact and conductive in the state shown in Figure 3A, and separated and not conductive in the state shown in Figure 3B. In this way, ultrasonic waves can be transmitted from the ultrasonic transducer 50 only when the administration lumen 10a in the closed state shown in Figure 3A, without using the sensor 25.

[0058] The ultrasonic transducer 50 may be supported at any other position on the deformable member 30, as long as it can transmit ultrasound toward the distal side A1 in the longitudinal direction A. Alternatively, the ultrasonic transducer 50 may be supported on the catheter body 10.

[0059] The ultrasonic transducer 50 may comprise, for example, a main body and electrodes. The main body may include a piezoelectric element. The piezoelectric element may include, for example, a piezoelectric material such as ceramics or quartz.

[0060] As shown in Figures 3A and 3B, the valve member 70 in this embodiment is connected to the deformation member 30 through the side hole 10a2 of the catheter body 10. As a result, the valve member 70 can move in the longitudinal direction A as the deformation member 30 deforms in the longitudinal direction A. By moving in the longitudinal direction A, the valve member 70 can open and close the administration lumen 10a.

[0061] Specifically, in this embodiment, the valve member 70 can switch the administration lumen 10a from a closed state to an open state by deforming in the longitudinal direction A against an elastic force when the deformable member 30 receives an external force directed toward the distal side A1 in the longitudinal direction A. More specifically, the deformable member 30 in this embodiment receives an external force directed toward the distal side A1 in the longitudinal direction A and deforms by stretching toward the distal side A1. As a result, the valve member 70 in this embodiment moves toward the distal side A1 in the longitudinal direction A from a position that closes the administration lumen 10a (see Figure 3A) to a position that opens the administration lumen 10a (see Figure 3B). When the deformable member 30 is no longer receiving an external force directed toward the distal side A1 in the longitudinal direction A, the deformable member 30 contracts toward the proximal side A2 due to an elastic force (restoring force). Therefore, the valve member 70 in this embodiment moves again to the proximal side A2 in the longitudinal direction A, from the position that opens the administration lumen 10a (see Figure 3B) to the position that closes the administration lumen 10a (see Figure 3A). As described above, the external force that deforms the deformation member 30 against the elastic force is the pressure due to blood flow. In this way, the blood flow timing and the administration timing can be synchronized.

[0062] As described above, the ultrasonic transducer 50 of this embodiment can transmit ultrasound toward the distal side A1 in the longitudinal direction A when the administration lumen 10a is closed (see Figure 3A). In this way, as described above, drug delivery through the vascular endothelium in areas within blood vessel BV (see Figure 1) where direct insertion of the catheter 100 is difficult can be made more efficient. Furthermore, the ultrasonic transducer 50 of this embodiment can transmit ultrasound toward the distal side A1 in the longitudinal direction A not only when the administration lumen 10a is closed (see Figure 3A), but also when the administration lumen 10a is open (see Figure 3B). In other words, the ultrasonic transducer 50 can transmit ultrasound toward the distal side A1 in the longitudinal direction A in both the closed state (see Figure 3A) and the open state (see Figure 3B) of the administration lumen 10a. In this way, as described above, control of the ultrasonic transducer 50 by the control device 301 becomes easier.

[0063] As shown in Figures 3A and 3B, the valve member 70 of this embodiment comprises a valve body 71 and a valve support portion 72. The valve support portion 72 supports the valve body 71. The valve support portion 72 is also connected to the deformation member 30 through the side hole 10a2 of the catheter body 10. More specifically, the valve support portion 72 of this embodiment is connected to the deformation member 30 by being formed integrally with the sliding portion 32 of the deformation member 30. The valve support portion 72 of this embodiment comprises a cylindrical portion 72a positioned within the administration lumen 10a such that its central axis aligns with the longitudinal direction A, and a connecting portion 72b that protrudes radially outward from the cylindrical portion 72a in the radial direction C and is connected to the sliding portion 32 through the side hole 10a2. The valve body 71 of this embodiment is attached to the base end of the valve support portion 72. More specifically, the valve body 71 of this embodiment is attached to the base end of the cylindrical portion 72a of the valve support portion 72. The valve member 70 of this embodiment comprises a plurality of valve bodies 71 (three in this embodiment). The plurality of valve bodies 71 are attached to the base end of the cylindrical portion 72a of the valve support portion 72 at different positions in the circumferential direction B. The configuration of the valve body 71 is not particularly limited, as long as it can open and close the administration lumen 10a. The valve body 71 may be, for example, an elastically deformable membrane. The number of valve bodies 71 is also not particularly limited.

[0064] [Control device 301] The control device 301 of this embodiment is connectable to the catheter 100. More specifically, the control device 301 of this embodiment is connectable to the first connection portion 21a of the hub 21 of the catheter body 10. By connecting the control device 301 to the first connection portion 21a, the control device 301 is electrically connected to the ultrasonic transducer 50 via the signal line 51.

[0065] As described above, the control device 301 can control the transmission of ultrasound from the ultrasonic transducer 50. Specifically, the control device 301 of this embodiment can control the transmission of ultrasound from the ultrasonic transducer 50 based on the open / closed state of the administration lumen 10a.

[0066] More specifically, the control device 301 of this embodiment controls the ultrasonic transducer 50 to transmit ultrasound toward the distal side A1 in the longitudinal direction A, in both the closed state of the administration lumen 10a (see Figure 3A) and the open state of the administration lumen 10a (see Figure 3B). However, as described above, the control device 301 may control the ultrasonic transducer 50 to transmit ultrasound toward the distal side A1 in the longitudinal direction A when the administration lumen 10a is closed (see Figure 3A), and may control the ultrasonic transducer 50 not to transmit ultrasound toward the distal side A1 in the longitudinal direction A when the administration lumen 10a is open (see Figure 3B).

[0067] The control device 301 includes a processor such as a general-purpose processor like a CPU (central processing unit) or an MPU (Micro Processing Unit), or a dedicated processor specialized for a specific process. The control device 301 of this embodiment may further include a storage unit such as a ROM (read-only memory) or RAM (random access memory).

[0068] [Pharmaceutical Supply Department 302] The drug supply unit 302 is connectable to the catheter 100. Specifically, the drug supply unit 302 in this embodiment is connectable to the second connection part 21b of the hub 21 of the catheter body 10. By connecting the drug supply unit 302 to the second connection part 21b, the drug supply unit 302 can supply drug to the administration lumen 10a. The drug supply unit 302 may be a known device capable of supplying drug by means of, for example, a pump.

[0069] [Air bubble supply unit 303] The bubble supply unit 303 is connectable to the catheter 100. Specifically, the bubble supply unit 303 in this embodiment is connectable to the second connection part 21b of the hub 21 of the catheter body 10. By connecting the bubble supply unit 303 to the second connection part 21b, the bubble supply unit 303 can supply microbubbles X (see Figure 1) to the administration lumen 10a. The configuration of the bubble supply unit 303 is not particularly limited as long as it can supply microbubbles X to the administration lumen 10a. The bubble supply unit 303 may be a known device capable of supplying a fluid containing microbubbles, for example, by a pump.

[0070] Next, with reference to Figures 5A and 5B, a catheter 200 as another embodiment of the catheter according to this disclosure will be described. Figures 5A and 5B are cross-sectional views of the tip of the catheter 200. Figure 5A shows the state in which the valve member 270 is open to the administration lumen 10a. Figure 5B shows the state in which the valve member 270 is closed to the administration lumen 10a. The catheter 100 described above (see Figures 1 to 4) is configured so that the blood flow timing and the administration timing coincide, whereas the catheter 200 of this embodiment is configured so that the blood flow timing and the administration timing do not coincide. Specifically, the catheter 200 of this embodiment differs from the catheter 100 described above (see Figures 1 to 4) in that the position of the annular flange 220a of the catheter body 210 and the position of the valve body 271 of the valve member 270 are different, but the other configurations are the same. Here, we will only explain the differences between the catheter 200 and the catheter 100 (see Figures 1 to 4) mentioned above, and will omit the explanation of the components that are common to both.

[0071] As shown in Figures 5A and 5B, the catheter 200 of this embodiment comprises a catheter body 210, a deformation member 30, an ultrasonic transducer 50, and a valve member 270. The deformation member 30 and the ultrasonic transducer 50 of this embodiment are the same as those in the catheter 100 described above (see Figures 1 to 4), so their explanation is omitted here.

[0072] The catheter body 210 is provided with an annular flange 220a that protrudes inward in the radial direction C. More specifically, the tubular body 20 of the catheter body 210 in this embodiment is provided with an annular flange 220a that protrudes inward in the radial direction C. The annular flange 220a in this embodiment is located distal to the slit, which serves as the side hole 10a2, at A1. As shown in Figures 5A and 5B, the annular flange 220a defines a through hole 220a1 that penetrates in the longitudinal direction A on the inside of the radial direction C. This through hole 220a1 is part of the administration lumen 10a. The valve member 270 in this embodiment can occlude the administration lumen 10a by covering this through hole 220a1 from the proximal side A2 in the longitudinal direction A (see Figure 5B). Furthermore, the valve member 270 of this embodiment is spaced apart from the through hole 220a1 towards the proximal side A2, and does not cover the through hole 220a1 from the proximal side A2 in the longitudinal direction A, thereby allowing the administration lumen 10a to be opened (see Figure 5A).

[0073] The valve member 270 of this embodiment comprises a valve body 271 and a valve support portion 72. The valve support portion 72 of this embodiment is the same as the configuration in the catheter 100 described above (see Figures 1 to 4), so its description is omitted here. The valve body 271 of this embodiment is attached to the tip of the valve support portion 72. More specifically, the valve body 271 of this embodiment is attached to the tip of the cylindrical portion 72a of the valve support portion 72. The valve member 270 of this embodiment comprises a plurality of valve bodies 271 (three in this embodiment). The plurality of valve bodies 271 are attached to the tip of the cylindrical portion 72a of the valve support portion 72 at different positions in the circumferential direction B. The configuration of the valve body 271 is not particularly limited as long as it can open and close the administration lumen 10a. The valve body 271 may be, for example, an elastically deformable membrane. The number of valve bodies 271 is also not particularly limited.

[0074] As shown in Figures 5A and 5B, the valve member 270 of this embodiment can switch the administration lumen 10a from an open state to a closed state by deforming the deformable member 30 in the longitudinal direction A against an elastic force when an external force is applied toward the distal side A1 in the longitudinal direction A. Specifically, the deformable member 30 of this embodiment receives an external force applied toward the distal side A1 in the longitudinal direction A and elongates toward the distal side A1. As a result, the valve member 270 of this embodiment moves toward the distal side A1 in the longitudinal direction A from a position that opens the administration lumen 10a (see Figure 5A) to a position that closes the administration lumen 10a (see Figure 5B). When the deformable member 30 is no longer receiving an external force applied toward the distal side A1 in the longitudinal direction A, the deformable member 30 contracts toward the proximal side A2 due to an elastic force (restoring force). Therefore, the valve member 270 in this embodiment moves again to the proximal side A2 in the longitudinal direction A, from the position that closes the administration lumen 10a (see Figure 5B) to the position that opens the administration lumen 10a (see Figure 5A). The external force that deforms the deformation member 30 against the elastic force is, as described above, the pressure due to blood flow. In this way, the timing of blood flow and the timing of administration can be kept separate.

[0075] In this case, the administered substance is administered when there is no blood flow and not when there is blood flow. Therefore, the administered substance administered when there is no blood flow remains near the outlet 10a1 of the catheter body 210, but this remaining administered substance moves downstream of the vascular BV (see Figure 1) by riding the blood flow when there is blood flow. In other words, even with such a catheter 200, just like the catheter 100 described above (see Figures 1 to 4), it is possible to efficiently deliver drugs from inside the vascular BV to cells and tissues outside the vascular BV in areas within the vascular BV where direct insertion is difficult.

[0076] Furthermore, the ultrasonic transducer 50 of this embodiment can also transmit ultrasound toward the distal side A1 in the longitudinal direction A when the administration lumen 10a is closed (see Figure 5B). This makes it possible to efficiently deliver drug solution through the vascular endothelium in areas within blood vessel BV (see Figure 1) where it is difficult to directly insert the catheter 200. However, the ultrasonic transducer 50 of this embodiment is controlled by the control device 301 (see Figure 1) to transmit ultrasound toward the distal side A1 in the longitudinal direction A only when the administration lumen 10a is closed (see Figure 5B). In other words, the ultrasonic transducer 50 of this embodiment is controlled by the control device 301 (see Figure 1) not to transmit ultrasound toward the distal side A1 in the longitudinal direction A when the administration lumen 10a is open (see Figure 5A). This prevents ultrasound from being transmitted from the ultrasonic transducer 50 when the administered substance is accumulating near the outlet 10a1 of the catheter body 210. Then, after the retained administered substance has moved downstream of the vascular BV by the blood flow timing, the ultrasonic transducer 50 can transmit ultrasound. As a result, as described above, drug delivery from within the vascular BV to cells and tissues outside the vascular BV can be made more efficient, even in areas within the vascular BV where direct insertion of the catheter 200 is difficult.

[0077] Next, with reference to Figure 6, a catheter 700 as another embodiment of the catheter according to the present disclosure will be described. Figure 6 is a diagram showing a catheter system 600 as one embodiment of the catheter system according to the present disclosure, including the catheter 700. As shown in Figure 6, the catheter system 600 comprises the catheter 700, a control device 301, a drug supply unit 302, and a bubble supply unit 303. Figure 6 shows the catheter 700 inserted into a blood vessel BV.

[0078] The control device 301, drug supply unit 302, and bubble supply unit 303 of the catheter system 600 in this embodiment are the same as those of the catheter system 300 described above (see Figure 1), so their description is omitted here. Furthermore, the catheter 700 in this embodiment differs from the catheter 100 described above (see Figures 1 to 4) only in the presence or absence of the mesh tube 90. Therefore, only the above-mentioned difference of the catheter 700 will be described here, and the configuration common to the catheter 100 described above (see Figures 1 to 4) will be omitted.

[0079] The mesh tube 90 in this embodiment is attached to the catheter body 10 so as to be able to change shape between a housing configuration in which it is housed in the administration lumen 10a (see Figure 3A, etc.) and a protruding configuration in which it protrudes to the distal side A1 in the longitudinal direction A through the outlet 10a1. Figure 6 shows the protruding configuration of the mesh tube 90.

[0080] As shown in Figure 6, the mesh tube 90 is expandable in its protruding form to a position radially C outside the ultrasonic transducer 50. The expansion of the mesh tube 90 in its protruding form may be self-expansion, for example, by the restoring force of the mesh tube 90 itself, or it may be balloon expansion, where it is expanded by being pushed out by a balloon. In this embodiment, the mesh tube 90 has a funnel-shaped outer shape in its protruding form, but it may have other outer shapes as long as it is expandable in its protruding form to a position radially C outside the ultrasonic transducer 50. In its protruding form, the mesh tube 90 may have a tapered outer shape, for example, where the outer diameter increases toward the distal side A1 in the longitudinal direction A. In this way, by expanding the mesh tube 90 in its protruding form to a position radially C outside the ultrasonic transducer 50, the mesh tube 90 comes into contact with the inner surface of the blood vessel BV. Therefore, the ultrasonic transducer 50 becomes less likely to come into contact with the inner surface of the blood vessel BV. This prevents the heat and vibration of the ultrasonic transducer 50 from being transmitted to the inner surface of the blood vessel BV. In other words, it protects the blood vessel BV from the heat and vibration of the ultrasonic transducer 50. Furthermore, it prevents the ultrasonic waves transmitted from the ultrasonic transducer 50 from propagating in directions other than the longitudinal direction A.

[0081] The wires constituting the mesh tube 90 are preferably made of a material having sufficient elasticity. Examples of materials that can be used to make the wires constituting the mesh tube 90 include various metals such as stainless steel, Ni-Ti alloy, Cu-Zn alloy, Ni-Al alloy, tungsten, tungsten alloy, titanium, titanium alloy, and tantalum, as well as relatively high-rigidity polymer materials such as polyamide, polyimide, ultra-high molecular weight polyethylene, polypropylene, and fluororesin, or combinations thereof as appropriate.

[0082] The catheters and catheter systems relating to this disclosure are not limited to the specific configurations described in the embodiments above, and various modifications, changes, and combinations are possible as long as they do not depart from the scope of the claims. For example, the catheter 700 (see Figure 6) of the catheter system 600 described above has a configuration in which a mesh tube 90 is added to the catheter 100 (see Figures 1 to 4) described above, but is not limited to this configuration. The catheter 700 (see Figure 6) may also have a configuration in which a mesh tube 90 is added to the catheter 200 (see Figures 5A and 5B) described above. [Industrial applicability]

[0083] This disclosure relates to catheters and catheter systems. [Explanation of Symbols]

[0084] 10: Catheter body 10a: Administration lumen 10a1: Outlet 10a2: Side hole 10b: Tip surface of the catheter body 11: Insertion lumens 20: Tubular body 20a: Annular flange 20a1: Through hole 20b: Annular flange 21: Hub 21a: First connection section 21b: Second connection section 21c: Hub body 25: Sensor 30: Deformed member 31: Bellows-like section 32: Sliding part 50: Ultrasonic transducer 51: Signal line 70: Valve component 71: Valve body 72: Valve support 72a: Cylindrical section 72b: Connection part 90: Reticular cylinder 100: Catheter 200: Catheter 210: Catheter body 220a: Annular flange 220a1: Through hole 270: Valve component 271: Valve body 300: Catheter System 301: Control device 302: Pharmaceutical Supply Department 303: Bubble supply unit 600: Catheter System A: Long direction A1: Distal side A2: Proximal side B: Circumferential direction C: Radial direction X: Microbubbles BV: Blood vessel

Claims

1. A catheter body comprising an internally partitioned administration lumen through which the administered substance can pass, and an outlet formed therein for discharging the administered substance from the administration lumen, A deformable member is attached to the catheter body so as to be located radially outside the catheter body and elastically deformable in the longitudinal direction of the catheter body, An ultrasonic transducer supported by the catheter body or the deformable member, capable of transmitting ultrasonic waves toward the distal end in the longitudinal direction, A catheter comprising a valve member capable of opening and closing the administration lumen in accordance with the longitudinal deformation of the deformable member.

2. The catheter body has a side hole connected to the administration lumen. The valve member is connected to the deformation member through the side hole, The catheter according to claim 1, wherein the valve member moves in the longitudinal direction in accordance with the longitudinal deformation of the deformable member, thereby enabling the administration lumen to be opened and closed.

3. The valve member is Valve body and, The catheter according to claim 2, further comprising a valve support portion that supports the valve body and is connected to the deformable member through the side hole.

4. The valve member is such that the deformable member receives an external force directed toward the distal side in the longitudinal direction and deforms in the longitudinal direction against elastic force, thereby enabling the administration lumen to be switched from a closed state to an open state. The catheter according to any one of claims 1 to 3, wherein the ultrasonic transducer is capable of transmitting ultrasound toward the distal side in the longitudinal direction when the administration lumen is closed.

5. The catheter according to claim 4, wherein the ultrasonic transducer is capable of transmitting ultrasound toward the distal side in the longitudinal direction when the administration lumen is open.

6. The valve member is such that the deformable member receives an external force directed toward the distal side in the longitudinal direction and deforms in the longitudinal direction against elastic force, thereby enabling the administration lumen to be switched from an open state to a closed state. The catheter according to any one of claims 1 to 3, wherein the ultrasonic transducer is capable of transmitting ultrasound toward the distal side in the longitudinal direction when the administration lumen is closed.

7. The aforementioned deformed member is The proximal end is fixed to the catheter body, and the bellows-like portion is elastically deformable by expanding and contracting in the longitudinal direction, A catheter according to any one of claims 1 to 3, comprising: a sliding part attached to the tip of the bellows-like part, which is movable in the longitudinal direction by sliding against the outer surface of the catheter body as the bellows-like part expands and contracts.

8. The catheter according to any one of claims 1 to 3, wherein the ultrasonic transducer is supported by the deformable member.

9. The outlet is formed on the tip surface of the catheter body. The catheter body is further equipped with a mesh tube that is shaped to change between a housing form that is housed in the administration lumen and a protruding form that protrudes toward the distal side in the longitudinal direction through the outlet, The catheter according to any one of claims 1 to 3, wherein the mesh tube is expandable in the protruding form to a position radially outward from the ultrasonic transducer.

10. A catheter according to any one of claims 1 to 3, A catheter system comprising a control device that can be connected to the catheter and can control the transmission of ultrasound from the ultrasonic transducer based on the open / closed state of the administration lumen.

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